Molybdenum carbide/molybdenum nitride hybrid N-doped graphene (abbreviated as Mo₂C/MoN/NG), as an efficient electrocatalyst for the hydrogen evolution reaction (HER), was synthesized via simple ion-exchange resin synthesis followed by a two-step annealing process, which increased the dispersion degree of the electrocatalyst’s active sites on the support skeleton and simplified the synthetic conditions. Additionally, N-doped graphene (NG) enhanced the electron transfer and reduced the inner resistance. The material has a graphene-like morphology and highly dispersed Mo2C/MoN nanoparticles about 2 nm in diameter on the NG. X-ray photoelectron spectroscopy, X-ray diffraction, and high-resolution transmission electron microscopy revealed that Mo₂C/MoN/NG consisted of Mo₂C and MoN composited together. Finally, Mo₂C/MoN/NG exhibited remarkable performance as an electrocatalyst for the HER with a small overpotential of 78.82 mV and a small Tafel slope of 39.3 mV·dec⁻¹ in a 0.5 mol·L⁻¹ H₂SO₄ solution. Its activity was approximately 30% lower than that of 20% Pt/C and 60% higher than that of NG. Also, it exhibited a low onset overpotential of 24.82 mV, which is similar to the theoretical HER potential. Our work provides a foundation for advanced HER applications of molybdenum compounds.

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通过简单的离子交换树脂合成，然后通过两步合成，合成了碳化钼/氮化钼杂化的N掺杂石墨烯（缩写为Mo ₂ C / MoN / NG），作为一种高效的氢析出反应（HER）电催化剂。退火过程提高了电催化剂活性部位在载体骨架上的分散度，简化了合成条件。此外，N掺杂的石墨烯（NG）增强了电子传输，并降低了内部电阻。该材料具有类似于石墨烯的形态，并且在NG上直径约2 nm的高度分散的Mo2C / MoN纳米颗粒。X射线光电子能谱，X射线衍射和高分辨率透射电子显微镜表明，Mo ₂ C / MoN / NG由Mo _2组成C和MoN合成在一起。最后，在0.5mol·L ^-1 H ₂ SO ₄溶液中，Mo ₂ C / MoN / NG作为HER的电催化剂表现出优异的性能，其小电势为78.82 mV，Tafel斜率为39.3 mV·dec ^-1。。它的活性比20％Pt / C的活性低约30％，比NG的活性高60％。此外，它还表现出24.82 mV的低起始过电势，与理论HER电势相似。我们的工作为钼化合物的高级HER应用奠定了基础。

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